A normal coal power plant can range from 500MW to over 5000 MW. "Noor 1, the first section at the town of Ouarzazate, provides 160 megawatts (MW) of the ultimate 580MW capacity" The one I worked at had 3 ~750MW generators. Its going to take a lot of solar to replace coal, nuclear is really the only way togo.

Nuclear power is extremely expensive and has its own problems. Any eventual solution of getting us away from fossil fuel use in the grid is going to almost certainly going to use a mix of sources, wind, nuclear, solar, along with geothermal, hydroelectric and tidal where geographically appropriate, together with improved transmission and storage systems.